Yes I am in Europe.
I will not die without AWS, but the same way I will not die without AWD. That does not mean AWD cannot be beneficial, nor that AWS is not beneficial. Subaru made AWD cars long before any other car makers, and made it their USP. Customers (not enthusiast) are not always informed about new technology/features, but were recently 'sold' AWD as the latest German thing (Quattro/xDrive/4Matic) that will make you drive like Alonso in any condition (not true). I have always liked the possibilities given by AWS (passive/active mechanical/electric rear wheel-steering), and the Japanese, especially Honda made it on many cars. AWS is not crucial, but better than many other features for me, so would come top on the list of not necessary features. The problem I have, it the Germans will sell AWS as the next best thing, and they were 'first'. VAG has AWS on all its expensive cars and it will trickle down on the next A4. I also expect the next 3 Series to get AWS optionally, it will no more be related to the FWD 1 Series, but the RWD 5 Series. Normal customer will never know that Talisman also has AWS (or had it before). Normal customer will not know that even the Megane in RS guise, has AWS. Nothing can beat German marketing, I and dislike it, because it is deceptive. I also dislike feature 'brands', like 4Control, Renault's rear-wheel-steering. Which customer can understand what it means? And without repeating it like the Germans, a customer will not remember. Every generic customer that has once shopped for a new car, and considered AWD, has heard of Quattro. Porsche for example is also guilty of dumbing down customers, with all their abbreviations, when all the customer cares about is the Porsche badge. Only those interested/working in the field know what something stands for and what it really does.
Why I mention AWS with regards to the ES, is because according to Lexus, whether it replaces the GS' customers or not, the goal is to bring a younger customer. I expect the ES to be not only comfortable, but also sportier and better handling. AWS, with would help. AWD more helps with grip, not handling (unless torque vectoring).
PS: I am not bashing German engineering. They are very good, world class at machinery, components, automation, whatever a lot of high tech, but cars are not what they do well/better than others. Their carmakers are specially good at marketing. Their 'deceptive' marketing (and other dirty tricks, hint: media) blows everything out of the water.